All instruments in the Target Range come complete with sensors or transducers as appropriate and all necessary fittings. They are designed to run on 12v supply, but due to the very low power consumption there is no reason why they cannot run off dry batteries. They provides accurate readings for owners of sailing craft and powerboats alike.
The biggest selling marine instrument world-wide is still the depth Sounder. In the Nasa Target Depth System you will find all the necessary features of much higher priced units including keel offset, shallow and deep water alarms, and a depth range of 1 - 100 metres.